Relay



Sept. 22, 1931. LD 1,824,131

FIG. 1.

RELAY Filgd Aug. 13, 1.930 2 Sheets-Sheet l m u n v O h u-g u 8 O O :1 i:

N O s o n O n INVENTOR ATTORNEY Sept. 22, 1931. Q s HELD 1,824,131

RELAY Filed Aug. 13, 1930 2 Sheets-Sheet 2 INVENTOR Patented Sept. 22, 1931 UNITED STATES PATENT OFFICE OSCAR S. FIELD, OF ROCHESTER, YORK, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW YORK 7 7 RELAY Application filed August 13, 1930. Serial N0. 474,958.

This invention relates to interlocking relays and more particularly to the type of interlocking relays which are used to control a signal at a highway crossing to give warning of an approaching train.

A visible or audible signal is often required at points 011 highways which cross railroad tracks at the same grade. These signals are usually controlled by relays which are governed by the passage of trains over two adjoining insulated track sections extending a predetermined distance in either direction from the highway. When the traffic moves in both directions over these track sections, it is necessary to have the train approaching the crossing from either direction operate the signal when in the particular section approaching the crossing, and it is advisable that the operation be discontinued when the train passes the crossing.

To accomplish this the signal is usually directly controlled by an interlocking relay, which consists of two relays with the operating coils of each relay each connected across the rails of one of the track sections at the crossing end. The far end of each of these track sections has a battery connected across the rails so that each of the two relays are normally energized and their armatures in a raised position. These two relay mechanisms are so arranged that the operation of one mechanically or otherwise determines the operation of the other forming in combination an interlocking relay.

The principal objects of this invention are to improve and simplify the interlocking mechanism of a relay of this type with the view of obtaining more reliable operation and to provide an apparatus adaptable to relays of commercial construction.

Other objects, purposes and characteristic features of the invention will appear as the description of the invention progresses.

In describing the invention in detail, reference will be made to the accompanying drawings, in which z- Fig. l is a fragmentary View in perspective of an interlocking relay according to this invention.

Fig. 2 is a diagram showing of an interend to end on a common base (not shown).

The construction of these neutral relays A and B is well known and consequently have not been shown in full. Each relayincludes two operating coils, one coil 0 being shown in place and the others omitted forsimplicity. The coils 0 are each wound around cores l2, and 1 2 respectively which cores are strapped together at one end by cross members 3 and 4:, fastened by a suitable bolt 5, and terminate in enlarged ends or pole faces. I

Armatures a and a are pivotally supported on stationary members 6 and 6 by pins 7 and 7 on one side, and a like support on the others, are arranged to swing into contact with the pole faces of cores l2, and 11-2 Control contactarms, such as 8 and 8 which are shown in full, are mounted on the armatures a and a and carry suitable low resistance contact points which engage with stationary contacts 9-10 and 9 --1() depending on the position of the armatures a and a the contacts being shown conventionally as arrows.

The armatures of the relays Aand B are mechanically interlocked by means consisting of a stationary supporting member 11, pivotally supporting two bell crank shaped locking dogs 12 and 13, by pins 14 and, 15 respectively. A front support for pins 14 and 15 is provided by member 16 suitably fastened to supporting member 11 by studs 17. The locking dogs 12 and 13 are counterweighted with suitable bosses 18 and 19 respectively to ordinarily maintain a position against stop 20 in supporting member 11.

The armature a has a rigidly mounted extension 21 engaging locking dog 12 on shoulder 22, and armature a of relay A has a similar extension 23 engaging locking dog 13 on shoulder 24.

A section of a railroad track each side of a hi hway crossing is shown in Fig. 2. This track is shown divided into two track sections by insulated rail joints I which are so located as to divide the sections at the point of highway crossing. The coils of relay A are connected across the rails of the track section at the crossing end of the section at the right,.and in like manner the coils of relay B are connected to the section at the left. Each of the relays A and Bare normally energized by current flowing through the rails which is supplied by a track battery B connected across, the-rails at the far end of each section. The signal S is shown for convenience as being a light signal energized by battery 5 and controlled directly by relays A andB through contacts and 10 connected in multiple.

The normal position for lockingdogs 12 and 13 is shown in Fig. 3 in which the relays A and B are energized holding their respective armature extensions 23 and 21 clearof shoulders 24 and--22 on the locking dogs.

' This causes the counterweightedbosses 18 and 19 to hold their respective locking dogs against stops 20.--

If a west-bound train enters the track section-at the right, the rails are shunted by '-the' wheels and axles of the train causing the relay A to be de-energized. The armature a then falls, closing a circuit to thesignal S as follows-:Beginning at battery 7), wires 25' and 26, contact 8 and contact 10 wire 27, :Esignal lamp S, wire 28 back to battery I).

*The, armature a ,tallin'g to its lower -posi tion-causes the extending member 23 to rotate the lockingdog 13 about pivot pin into a position asshown in Fig.- 4. When the head endof the train enters the second track section, the rails of that section are likewise shunted-andtherelay B is de-energized, but thetalling of armature a of relay A has ro tatcd th-e'locking dog 13 far enough lito bring its-heel 13 into the path of the locking dog l2 (see Fig.- 5) thereby blocking it fromrotatingabout its pivot pin 1d and thus preventing the armature extension 21 from swinging downwardly. The armature a of relay Btherefore does not drop although deenergized, and the relay A is the onlyone now controlling signal S.

After the rear of the train has passed the a crossing, and providing another train is not occupying the first track section, the shunt is removed from the rails and relay A is again energized. The armature a of this relay is thus raised which action interrupts the circuit to signal S and lifts armature extension 23v to its raised position. The locking dog 13, however, does not follow the armature extension 23 back to its raised position, it being retained in a position as shown in Fig. 6, by an upstanding hook 29 on the end of locking dog 12 engaging the heel 13 of the locking dog 13.

In the event of a second train entering the first track section before the first train has cieared the second track section, the signal will again be operated inasmuch as the locking dog 13 is retained in a downward position by the locking dog 12, as just described, and does not prevent the armature of relay A from falling. V

W hen both track sections are clear of trains, their corresponding relays will again be energized and the armature extension 21 0t relay-Bis raised clear of locking dog 12. Locking dog 12 swings back about its pivot pin 14 to a position against. stop releasing the latch 29 and allowing locking dog 13 to swing back against stop 20..

It is evident that the first relay to be deenergized is the only; one which governs the operation of the signal, and that a similar operating cycle is obtained independently of.

the direction from which the train approaches the crossing.

Having thus shown and described one specific embodiment of the present invention, it

is desired to be understood that various adaptations and alterations may be applied to the specific form shown to meet the requirement of practice, Without in any mannerdeparting from the spirit or scope of the present invention except as limited by the appendedclaims. Having thusdescribed my invention, what I claim is 1. An interlocking relay comprising two neutral armatures, each of said armatures having individual; electro-inagnetic actuating means, an extending arm attached to each of said armatures, two locking dogs, each of said locking dogshaving pivot supporting means for engaging the heel of the locking dog first operated by thehook of the locking dog last operated.

2. An. interlocking relay COIHPIlSlIlgIWO neutral armatures, each of said armatureshavingindividual electro-magnetic actuating.

having theirrespective. centers of gravity so located with respect to their pivot-to bias said dogs away; from each other, each of said locking dogs including a downward extending leg, said leg having a heel and a hook, a shoulder on each of said locking dogs on the outside of said pivot supporting means and engageable by said armature arm, means for restricting the movement of one of said locking dogs by a previous movement of the other of said locking dogs, and means effective after the operation of both locking dogs for engaging the heel of the locking dog first operated by the hook of the locking dog last operated.

In testimony whereof I aifix my signature.

OSCAR S. FIELD. 

